Method for manufacturing passive optical components, and devices comprising the same

ABSTRACT

A device comprises at least one optics member (O) comprising at least one transparent portion (t) and at least one blocking portion (b). The at least one transparent portion (t) is made of one or more materials substantially transparent for light of at least a specific spectral range, referred to as transparent materials, and the at least one blocking portion (b) is made of one or more materials substantially non-transparent for light of the specific spectral range, referred to as non-transparent materials. The transparent portion (t) comprises at least one passive optical component (L). The at least one passive optical component (L) comprises a transparent element ( 6 ) having two opposing approximately flat surfaces substantially perpendicular to a vertical direction in a distance approximately equal to a thickness of the at least one blocking portion (b) measured along the vertical direction, and, attached to the transparent element ( 6 ), at least one optical structure ( 5 ).

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of U.S. application Ser. No.14/288,755, filed on May 28, 2014, now U.S. Pat. No. 9,193,120, which isa continuation of U.S. application Ser. No. 13/553,385, filed on Jul.19, 2012, now U.S. Pat. No. 8,767,303, which claims the benefit ofpriority of U.S. Application No. 61/509,357, filed on Jul. 19, 2011. Thedisclosures of the prior applications are incorporated herein byreference.

TECHNICAL FIELD

This disclosure relates to the field of optics and more specifically tothe manufacturing of optical and opto-electronic components. It relatesto passive optical components and devices comprising these and to theirmanufacture.

BACKGROUND

In US 2011/0043923 A1, a way is described, of how passive opticalcomponents can be manufactured by means of replication. E.g., theforming by replication of lenses as a unitary parts is describedtherein.

In US 2011/0050979 A1, an optical module for an electro-optical devicewith a functional element is disclosed. In the manufacture of themodule, lens elements are produced on a transparent substrate. In orderto ensure an improved performance of the functional element, an EMCshield is provided. E.g., the substrate can, on one of its surfaces, beprovided with a layer of non-transparent, electrically conductivematerial having apertures for the lens elements. The manufacture of aplurality of such modules on a wafer scale is also disclosed in US2011/0050979 A1.

WO 2005/083789 A2 concerns a combination of passive optical elementswith active optoelectronics. An optoelectronic wafer comprising activeoptical components is provided with (micro-) optical structures, whereinthe optical structures are allocated to the active optical components.The optical structures are manufactured using replication.

DEFINITION OF TERMS

“Active optical component”: A light sensing or a light emittingcomponent. E.g., a photodiode, an image sensor, an LED, an OLED, a laserchip.

“Passive optical component”: An optical component redirecting light byrefraction and/or diffraction and/or reflection such as a lens, a prism,a mirror, or an optical system, wherein an optical system is acollection of such optical components possibly also comprisingmechanical elements such as aperture stops, image screens, holders.

“Opto-electronic module”: A component in which at least one active andat least one passive optical component is comprised.

“Replication”: A technique by means of which a given structure or anegative thereof is reproduced. E.g., etching, embossing, molding.

“Wafer”: A substantially disk- or plate-like shaped item, its extensionin one direction (z-direction or vertical direction) is small withrespect to its extension in the other two directions (x- andy-directions or lateral directions). For example, on a (non-blank)wafer, a plurality of like structures or items are arranged or providedtherein, e.g., on a rectangular grid. A wafer may have opening or holes,and a wafer may even be free of material in a predominant portion of itslateral area. Although in many contexts, a wafer is understood to beprevailingly made of a semiconductor material, in the present patentapplication, this is explicitely not a limitation. Accordingly, a wafermay prevailingly be made of, e.g., a semiconductor material, a polymermaterial, a composite material comprising metals and polymers orpolymers and glass materials. In particular, hardenable materials suchas thermally or UV-curable polymers are interesting wafer materials inconjunction with the presented invention.

“Lateral”: cf. “Wafer”

“Vertical”: cf. “Wafer”

“Light”: Most generally electromagnetic radiation; more particularlyelectromagnetic radiation of the infrared, visible or ultravioletportion of the electromagnetic spectrum.

SUMMARY

Some implementations provide one or more of the following advantages.For example, some implementations create an improved way ofmanufacturing passive optical components and devices comprising at leastone such passive optical component. More generally, a device and methodsfor manufacturing a device are disclosed, wherein the device comprisesat least one optics member and at least one passive optical component,respectively. The device and the passive optical component,respectively, can be identical with the device and the passive opticalcomponent, respectively, itself.

Also, some implementations provide a relatively simple way ofmanufacturing such devices and provide corresponding devices.

Further, some implementations provide a way of manufacturing suchdevices, in particular in large numbers, using a particularly smallnumber of manufacturing steps and providing corresponding devices.

Some implementations provide a particularly efficient way ofmanufacturing such devices and to provide corresponding devices. Inparticular, the assembly can be particularly efficient.

Some implementations provide a particularly cost-effective way ofmanufacturing such devices and to provide corresponding devices. Inparticular, the assembly can be particularly cost-effective.

Some implementations provide a particularly time-saving way ofmanufacturing such devices and provide corresponding devices.

Some implementations provide devices of particularly small outerdimensions and provide corresponding manufacturing methods.

Some implementations provide devices having a particularly high level ofintegration and to provide corresponding manufacturing methods.

Some implementations provide devices consisting of a particularly smallnumber of constituents and provide corresponding manufacturing methods.

Some implementations provide devices having a particularly accuraterelative positioning of individual optical components comprised in thedevice and provide corresponding manufacturing methods.

Some implementations provide devices having particularly good opticalproperties and provide corresponding manufacturing methods.

At least one of these objects is at least partially achieved by devicesand methods according to the patent claims.

The method for manufacturing a device comprising at least one passiveoptical component comprises:

-   a) providing a wafer comprising at least one blocking portion and a    multitude of transparent elements;    wherein each of the multitude of transparent elements is made of    transparent material substantially transparent for light of at least    a specific spectral range, and the at least one blocking portion is    made of non-transparent material substantially non-transparent for    light of the specific spectral range.

This can be useful in many aspects and applications and devices, as willbe become clear from the text below. E.g., an efficient manufacturing ofpassive optical components on wafer level can be accomplished this way,in particular wherein at least a portion of the passive opticalcomponents (in particular optical structures as described further below)extends vertically beyond the vertical extension of the surroundingwafer portions, the surrounding wafer portions being, for example,formed by the blocking portion.

The device can comprise at least a portion of the wafer.

Examples of lateral dimensions of the wafer are at least 5 cm or 10 cm,and up to 30 cm or 40 cm or even 50 cm; examples of vertical dimensionsare at least 0.2 mm or 0.4 mm or even 1 mm, and up to 6 mm or 10 mm oreven 20 mm.

For example, the passive optical component is provided for influencing,in particular for guiding light.

In some embodiments, each of the multitude of transparent elements islaterally adjacent to the at least one blocking portion.

In some embodiments which may be combined with the before-addressedembodiment, each of the multitude of transparent elements is laterallyencircled by the at least one blocking portion.

In some embodiments which may be combined with one or more of thebefore-addressed embodiments, the at least one blocking portion is madesubstantially of exactly one non-transparent material.

In some embodiments which may be combined with one or more of thebefore-addressed embodiments, a vertical extension of each of themultitude of transparent elements is at least approximately equal to avertical extension of the at least one blocking portion.

In some embodiments which may be combined with one or more of thebefore-addressed embodiments, each of the multitude of transparentelements has two opposing at least approximately flat surfacessubstantially perpendicular to a vertical direction.

In some embodiments which may be combined with one or more of thebefore-addressed embodiments, the method comprises the step of

-   d) manufacturing the wafer;    wherein step d) comprises the steps of    -   d1) providing a precursor wafer substantially made of the        non-transparent material having openings in places where the        transparent elements are supposed to be located;    -   d2) at least partially filling the openings with at least one of        the transparent materials.

This can be a particularly efficient way of manufacturing the wafer.

In some embodiments referring to the before-addressed embodiment, duringstep d2), the transparent materials are in a liquid or viscous state,and wherein subsequent to step d2), the step of

-   -   d3) hardening the transparent material;        is carried out. In particular, the hardening comprises curing.

In some embodiments referring to one or both of the two before-addressedembodiments comprising steps d1) and d2), step d2) is carried out usinga dispenser. Therein, one or several of the openings can be filled at atime.

An alternative to using a dispenser is using a squeegee process, e.g.,like used in a screen-printing process.

In some embodiments referring to one or more of the before-addressedembodiments comprising steps d1) and d2), the method comprises the stepof manufacturing the precursor wafer using replication. This can be veryefficient. When a hardening step is carried out during the replication,e.g., a curing step, this will rather by done by heating, because anon-transparency of the non-transparent material of the blocking portionmay in many cases be accompanied by a non-transparency for radiationthat would be used for accomplishing radiation hardening.

An alternative to replication is creating the openings by means ofdrilling or etching, or to manufacture the precursor wafer usingmolding. If molding is used, duroplastic injection molding can be aparticularly suitable method for various applications.

In some embodiments which may be combined with one or more of thebefore-addressed embodiments, the method comprises the step of

-   c) manufacturing an optics wafer comprising a multitude of passive    optical components comprising the at least one passive optical    component;    wherein step c) comprises the step of    -   c1) producing the multitude of passive optical components by        producing on each of the multitude of transparent elements at        least one optical structure.

For example, the at least one optical structure is provided forinfluencing, in particular for guiding light more particularly forredirecting light.

It is possible to provide that the device is or comprises the opticswafer or comprises a portion thereof.

In some embodiments referring to the before-addressed embodiment(comprising steps c) and c1)), the at least one optical structurecomprises at least one lens element.

This is an example application. The lens element can be a lens being aconstituent of a composed lens comprising in addition at least one ofthe transparent elements.

The lens element itself and a composed lens as mentioned before can workbased on refraction and/or on diffraction.

Instead of a lens element (or in addition thereto), other elements suchas a prism element may be comprised in the optical structure. And coatedelements may be suitable, too, e.g., a transparent part coated with areflective coating, serving as a mirror element.

In some embodiments referring to one or more of the before-addressedembodiments comprising steps c) and c1), the producing the opticalstructures (mentioned in step c1)) is carried out using replication.This is a very efficient and precise way of producing the opticalstructures.

For example, a replication material used for the replication issubstantially transparent for light of the specific spectral range (atleast when the replication material is in a hardened state). A way ofcarrying out the replication suitable for many applications comprisesembossing.

In some embodiments referring to the before-addressed embodiment, theproducing the optical structures using replication comprises the stepsof

-   r1) applying a replication material to each of the multitude of    transparent elements;-   r2) replicating a structured surface in the replication material;-   r3) hardening the replication material;-   r4) removing the structured surface.

Steps r1) to r4) can be subsequently carried out in the cited order orin the order r2, r1, r3, r4.

Replication material is a hardenable, for example, curable material; inparticular hardenable and curable, respectively, using ultravioletradiation or heating. Suitable replication materials can be, e.g.,polymers such as epoxy resins.

It is possible to provide that the producing the optical structure usingreplication is carried out in one replication process simultaneously forall of the optical structures. But it is also possible to provide thatthe producing the optical structures using replication is carried out bysubsequently carrying out a multitude of replication processes, such asone replication process for each of the optical structures, but possiblyone single replication process for a fraction of all of the opticalstructures.

In some embodiments referring to the before-addressed embodimentcomprising steps r1) to r4), the replicating mentioned in step r2) iscarried out in an aligned manner; more specifically such that thestructured surface is aligned in a well-defined manner with respect toat least one of the multitude of transparent elements.

In some embodiments referring to one or more of the before-addressedembodiments comprising steps c) and c1), the method comprises the stepof

-   e) preparing a wafer stack comprising the optics wafer and at least    one additional wafer;-   f) obtaining a multitude of separate modules each comprising at    least one of the multitude of passive optical components, by    separating the wafer stack.

In some embodiments referring to the before-addressed embodiment(comprising steps e) and f)), step e) comprises fixing, in particularbonding the wafers of the wafer stack with respect to each other, e.g.,by gluing, e.g., using a heat-curable epoxy resin.

In some embodiments referring to one or more of the before-addressedembodiments comprising steps e) and f), step e) comprises aligning thewafers of the wafer stack with respect to each other, in particular insuch a way that they are suitably aligned when fixing them with respectto each other.

In some embodiments which may be combined with one or more of thebefore-addressed embodiments comprising steps e) and f), at least one ofthe additional wafers comprises a multitude of active opticalcomponents, the separate modules each comprising at least one of themultitude of active optical components. Therein, for example, each ofthe transparent elements and passive optical components, respectively,is allocated with at least one of the multitude of active opticalcomponents; and this can be provided for during manufacturing byaligning the wafer accordingly.

In some embodiments which may be combined with one or more of thebefore-addressed embodiments comprising steps e) and f), at least one ofthe additional wafers is a spacer wafer structured and configured forproviding a well-defined vertical distance between the passive opticalcomponents and mechanical stops provided by the spacer wafer.

It is possible to provide that the device is or comprises the waferstack or comprises a portion thereof.

It is possible to provide that the device is or comprises one or atleast one of the modules.

In addition to the method addressed above, the invention also comprisesa device:

The device comprises at least one optics member comprising at least onetransparent portion and at least one blocking portion, wherein

-   -   the at least one transparent portion is made of one or more        materials substantially transparent for light of at least a        specific spectral range, referred to as transparent materials,        and the at least one blocking portion is made of one or more        materials substantially non-transparent for light of the        specific spectral range, referred to as non-transparent        materials,    -   the transparent portion comprises at least one passive optical        component, the at least one passive optical component comprises        a transparent element having two opposing at least approximately        flat surfaces substantially perpendicular to a vertical        direction, and, attached to the transparent element, at least        one optical structure.

The invention comprises devices with features of corresponding methodsaccording to the invention, and, vice versa, also methods with featuresof corresponding devices according to the invention.

The advantages of the devices basically correspond to the advantages ofcorresponding methods, and, vice versa, the advantages of the methodsbasically correspond to the advantages of corresponding devices.

In some embodiments, the transparent element is a unitary part.

In some embodiments which may be combined with the before-addressedembodiment, the passive optical component is not a unitary part. Itcomprises at least two constituents, e.g., two or three constituents.These can be, for example, the transparent element and the at least oneoptical structure.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, the two opposing at leastapproximately flat surfaces are arranged in a distance at leastapproximately equal to a thickness of the at least one blocking portionmeasured along the vertical direction.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, each constituent of each of thetransparent portions is made of one (single) transparent material,wherein these can be identical or different for one of more of theconstituents of each of the transparent portions.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, the at least one transparentportion is identical with the at least one passive optical component.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, the optics member without the atleast one optical structure is generally planar.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, the optics member without the atleast one optical structure is of generally block- or plate-like shape.

It is possible to provide that the device is one such optics members.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, the at least one blocking portionis made of a hardened hardenable material, in particular of a curedcurable material.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, the at least one blocking portionis manufactured using replication. An alternative method would be tostart from a blank wafer and use drilling or etching, or to use moldingfor manufacturing the at least one blocking portion.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, the transparent element is made ofa hardened hardenable material, in particular of a cured curablematerial. If the transparent element is manufactured using dispensing, ahardened hardenable dispensable material can be used. If the transparentelement is manufactured using a squeegee process, a hardened hardenablematerial applicable in a squeegee process can be used.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, the at least one optical structureis made of a hardened hardenable material, in particular of a curedcurable material.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, the passive optical componentcomprises at least one optical structure attached to each of theopposing surfaces, in particular, it comprises exactly one opticalstructure per opposing surface.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, the device comprises anopto-electronic module in which the at least one optics member iscomprised.

In some embodiments referring to the before-addressed embodiment, theopto-electronic module comprises at least one active optical component,in particular wherein in the opto-electronic module, the at least oneactive optical component and the at least one optics member are fixedwith respect to one another. For example, the opto-electronic module canbe a packaged component.

In some embodiments referring to one or both of the two last-addressedembodiments, the device is the opto-electronic module.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments comprising the opto-electronicmodule, the device comprises a printed circuit board on which theopto-electronic module is mounted. In particular, wherein the device isan electronic device.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments, the device comprises a waferreferred to as optics wafer, the optics wafer comprising a multitude ofthe optics members, in particular wherein the optics members arearranged (laterally) next to one another.

It is possible to provide that the device is or comprises the opticswafer.

In some embodiments referring to the before-addressed embodiment, thedevice comprises a wafer stack in which the optics wafer is comprised.It is possible to provide that the device is or comprises the waferstack.

In some embodiments which may be combined with one or more of thebefore-addressed device embodiments comprising the opto-electronicmodule, the device comprises a wafer stack in which a multitude of theopto-electronic modules is comprised, in particular wherein theopto-electronic modules are arranged (laterally) next to one another. Itis possible to provide that the device is or comprises the wafer stack.

Additional aspects, features and advantages of the invention will bereadily apparent from the detailed description, the accompanyingdrawings and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Below, examples of the invention are described in more detail withreference to the drawings. The figures show schematically:

FIG. 1 a diagrammatical illustration of a cross-section through a devicebeing a passive optical component;

FIG. 2 a diagrammatical illustration of a top view of the device of FIG.1;

FIG. 3 a diagrammatical illustration of a manufacturing step in across-sectional view;

FIG. 4 a diagrammatical illustration of a manufacturing step in across-sectional view;

FIG. 5 a diagrammatical illustration of a manufacturing step in across-sectional view;

FIG. 6 a diagrammatical illustration of a cross-section through a devicebeing an optics wafer;

FIG. 7 a diagrammatical illustration of a cross-section through a devicebeing an optics wafer;

FIG. 8 a diagrammatical illustration of a cross-section illustrating amanufacturing step;

FIG. 9 a diagrammatical illustration of a cross-section illustrating amanufacturing step;

FIG. 10 a diagrammatical illustration of a detail of a cross-sectionalview;

FIG. 11 a diagrammatical illustration of a detail of a cross-sectionalview;

FIG. 12 a diagrammatical illustration of a cross-section through adevice being an opto-electronic module illustrating a device being anelectronic device;

FIG. 13 a cross-sectional view of wafers for forming a wafer stack formanufacturing a multitude of modules of FIG. 12;

FIG. 14 a cross-sectional view of a device being a wafer stack formanufacturing a multitude of modules of FIG. 12;

FIG. 15 a diagrammatical illustration of a cross-section through adevice being a semi-finished part;

FIG. 16 a diagrammatical illustration of a cross-section through adevice being a semi-finished part.

The reference symbols used in the figures and their meaning aresummarized in the list of reference symbols. The described embodimentsare intended as examples.

DETAILED DESCRIPTION

FIG. 1 is a schematized diagrammatical illustration of a cross-sectionthrough a device being a passive optical component O. FIG. 2 is aschematized diagrammatical illustration of a top view of the device ofFIG. 1. Passive optical component O can and will also be referred to asoptics member O.

In FIG. 1, the vertical (z) direction is indicated, as well as the xdirection. The directions indicated in FIG. 2 (directions in the x-yplane) are referred to as lateral directions.

Optics member O comprises a blocking portion b and two transparentportions t. In fact: Optics member O consists of a blocking portion band two transparent portions t. Blocking portion b is made of amaterial, for example, a polymer material, which is substantiallynon-transparent for light of a specific spectral range (wavelength orwavelength range), whereas the transparent portions t are made of amaterial which is substantially transparent for light at least of thespecific spectral range. This way, blocking portion b functions as anaperture for each of the transparent portions t and also fixes (orholds) the transparent portions t. And, as will become clearer later(cf. FIG. 12), blocking area b can function as a shield for protectionfrom undesired light, by substantially attenuating or blocking light ofthe specific spectral range.

Each of the transparent portions t comprises at least two parts; in theexample of FIGS. 1 and 2, it is three parts: Two lens elements 5 (or,more generally: optical structures 5) and a transparent element 6.Together, these form a lens member L (or, more generally: a passiveoptical component). Optical structures 5 protrude from the surfacedescribed by the blocking portion b; in other words, they extendvertically beyond the level described by the blocking portion b. Whenthe optical structures 5 are lens elements (e.g., concave ones or, asshown in FIG. 1, convex ones) having at least one apex, these apices arelocated outside a vertical cross-section of the optics member O (FIG.1).

Blocking portion b together with transparent elements 6 describes a(close-to-perfect) solid plate-like shape. The optical structures 5protrude therefrom. Each of the transparent elements 6 has two opposinglateral surfaces which are substantially flat, i.e. two surfaces lyingsubstantially in the x-y plane.

The outer shape of optics member O is generally plate- or disk-like,with rectangular side walls.

Particularly interesting is the manufacturability of the optics membersO and of other devices according to the invention. In particular,wafer-level manufacturing is possible. This will be explained referringto FIGS. 3 to 14.

FIGS. 3 to 7 are schematized diagrammatical illustrations ofmanufacturing steps, in a cross-sectional view. FIG. 3 illustratesschematically a precursor wafer 8 made of non-transparent material,having a multitude of holes or openings 11. One or more of these arearranged, for example, on a rectangular lattice; since optics member Oof FIGS. 1 and 2 to be manufactured comprises two transparent portionst, these two are arranged on a rectangular lattice.

Precursor wafer 8 can be manufactured by replication, e.g., usingembossing or molding. Or a blank wafer can be provided with the openings11 by drilling or etching.

It is to be noted that the shape of the openings 11 in precursor wafer 8can of course be different from the cylindrical shape shown in FIGS. 1to 3. The holes 11 need not be prismatic having a vertical axis, and alateral cross-section does not have to be circular. E.g., ellipticshapes are possible; and the shape in a lateral cross-section may varyalong the vertical direction; and the area described by the holes 11 ina lateral cross-section may vary along the vertical direction.

In a next step (cf. FIG. 4), the transparent elements 6 are formed byfilling the openings 11 with a suitable transparent material T. Duringthe filling, the transparent material T, for example, a polymer, isliquid or viscous. A squeegee process similar to what is known fromscreen printing can be used, or a dispenser, e.g., like known fromsemiconductor industry and used for underfilling, can be used. Thedispensing can be carried out one-by-one, or several openings aresimultaneously filled, e.g., by using several hollow needles outputtingtransparent material T.

During the filling, the precursor wafer 8 lies on a support layer 12,e.g., made of a silicone such as polydimethylsiloxane. Support layer 12is supported by a rigid support substrate 13, e.g., a glass plate, formechanical stability.

During filling-in the transparent material T, care has to be taken orderto prevent the formation of air bubbles or cavities in the material T,because this would likely degrade the optical properties of the passiveoptical components L to be produced, since transparent element 6 is aconstituent thereof. E.g., one can carry out the dispensing in such away that wetting of the wafer material starts at an edge formed by theprecursor wafer 8 and the underlying support layer 12 or in a placeclose to such an edge; e.g., by suitably guiding a hollow needleoutputting the material T close to such an edge. This is visualized inFIGS. 8 and 9 which are schematized diagrammatical illustrations of across-section for illustrating this manufacturing step. Depending onproperties of the involved materials, more particularly of the surfacetensions of transparent material T, of the material of precursor wafer 8and of the material of support layer 12, the shapes described by thematerial T while being filled in into the holes 11 can vary and possiblylook similar to what is schematically illustrated in FIG. 8 and in FIG.9, respectively. The dashed lines indicate the time evolvement of theshape with increasing amount of filled-in material T, FIGS. 8 and 9illustrating different behavior for different wetting angles.

The filling-in is stopped when enough material T is filled in. Beforeproceeding, the filled-in transparent material T is hardened, e.g., bycuring it, e.g., using heat or UV radiation. It is possible, that theso-obtained transparent elements have two (nearly) perfectly planarlateral surfaces, in particular (nearly) perfectly forming a commonplanar surface with the surrounding (blocking) portion of the precursorwafer 8. But possibly, the filling, accomplished using a squeegee or bydispensing or accomplished differently, may be less perfect. Examplestherefor are shown in FIGS. 10 and 11, which are schematizeddiagrammatical illustrations of a detail of a cross-sectional view.E.g., a concave surface might be formed as illustrated in FIG. 10, or aconvex surface might be formed as illustrated in FIG. 11. In the convexcase, it can be advantageous to provide a polishing step beforecontinuing with the next manufacturing steps. By means of the polishing,it is possible to achieve that the protruding portion is taken down atleast partially. In addition, it is possible that polishing can removespilled-over transparent material, i.e. material which has not beendeposited in the desired location during filling-in, e.g., material thathas not been deposited on a transparent element, but, e.g., slightlynext thereto.

It is alternatively also possible to accomplish the formation of thetransparent elements 6 in a different fashion involving finishing stepsor not. By means of the support layer 12, it can be possible to ensure arather planar surface of the transparent material T at that side of thewafer, but other ways of accomplishing this might also be used.

When each of the openings 11 contains an appropriate amount of hardenedtransparent material T, optical structures 5 are applied thereto (cf.FIGS. 5 and 6). This can be accomplished, e.g., by replication, in a wayknown in the art, e.g., as described in WO 2005/083789 A2 or in US2011/0050979 A1. E.g., in a form having a structured surface describinga negative of the optical structures 5 to be produced, a suitable amountof a replication material provided, and then, the form with thestructured surface is moved towards the wafer, so as to get thereplication material in an appropriate contact with a transparentelement 6. Subsequently, the replication material is hardened, e.g.,cured, e.g., by heating or irradiating with light (such as UV light),and the form is removed. The formation of the optical structures 5 (byreplication or differently) may be accomplished one-by-one or several ata time (but only a fraction of all on one side of the wafer), orsimultaneously for all on one side of the wafer.

The optical structures 5 can be formed on one or on both sides of thewafer (cf. FIGS. 5 and 6). The lateral extension of the opticalstructures 5 can be larger or smaller than the lateral extension of thetransparent elements 6, or substantially be identical, as shown in FIGS.5 and 6. The optical structures 5 can be lens elements of virtually anyshape, be it refractive and/or diffractive lens elements, or prismelements or others. For many applications, lens elements are a suitablechoice.

The so-obtained optics wafer OW (cf. FIG. 6) can be a device itself andcan be used, e.g., for producing further products.

It is also possible to separate such an optics wafer OW into a multitudeof optics member like those shown in FIGS. 1 and 2, e.g., by dicing. InFIG. 7 showing a schematized diagrammatical illustration of across-section through a device being an optics wafer OW, the thin dashedrectangles indicate where separation can take place.

FIG. 12 is a schematized diagrammatical illustration of a cross-sectionthrough a device being an opto-electronic module 1 also illustrating adevice being an electronic device 10 comprising such an opto-electronicmodule 1 mounted on a printed circuit board 9 of the electronic device10. The electronic device 10 can be, e.g., a hand-held electroniccommunication device such as a smart phone, or a photographic devicesuch as a photo camera or a video camera.

The opto-electronic module 1 comprises an optics member O as shown inFIGS. 1 and 2 and also at least one active optical component such as adetector D (e.g., a photo diode) and a light emitter E (e.g., alight-emitting diode). The active optical components D, E are mounted ona substrate P provided with solder balls 7. Between substrate P andoptics member O, a separation member S (or spacer member S) withopenings 4 is arranged, i.a. for ensuring a suitable distance betweenthe active optical components D, E and the passive optical components L.On top, a baffle member B having transparent regions 3 is arrangedfunctioning as a baffle.

The substrate P, the optics member O, the baffle member B and theseparating member S are of generally block- or plate-like shape (whereinat least the separating member S and the baffle member B have at leastone hole each). This way, it is possible that a particularly goodmanufacturability is achieved.

There exists a specific wavelength range for which the passive opticalcomponents L and thus the transparent material T and the material ofwhich the optical structures 5 are made (which may be identical with ordifferent from material T) are transparent, but for which the materialof which the blocking portion b is made is non-transparent.

There is, e.g., if the opto-electronic module 1 is a proximity sensor,an overlapping wavelength range of the wavelength range of lightemittable by light emitter E and the wavelength range of lightdetectable by the light detector D. At least in that overlappingwavelength range, blocking portion b will be non-transparent, and atleast in a portion of the overlapping wavelength range, transparentportion t will be transparent. Note that the term wavelength range doesnot imply that it is contiguous. The overlapping wavelength range can bein the infrared portion and more specifically in the near-infraredportion of the electromagnetic spectrum. This can be particularly usefulfor proximity sensor.

An opto-electronic module 1 as shown in FIG. 12 can well be manufacturedon wafer-scale. Therein, optics wafers like shown in FIG. 6 can be used.

FIG. 13 is a schematized cross-sectional view of wafers for forming awafer stack 2 (cf. FIG. 14) for manufacturing a multitude of modules 1of FIG. 12.

Four wafers are sufficient for manufacturing a multitude of modules 1 asshown in FIG. 12: A substrate wafer PW, a spacer wafer SW, an opticswafer OW (like shown in FIG. 6) and a baffle wafer BW. Each wafercomprises a multitude of the corresponding members comprised in thecorresponding module 1 (cf. FIG. 12), arranged, for example, on arectangular lattice, e.g., with a little distance from each other for awafer separation step.

Substrate wafer PW can be a printed circuit board (PCB) of standard PCBmaterials, provided with solder balls 7 on the one side and with activeoptical components (E and D) soldered to the other side. The latter canbe placed on substrate wafer PW by pick-and-place using standardpick-and-place machines.

Ways of manufacturing optics wafer OW have been described above.

In order to provide maximum protection from detecting undesired light,all wafers PW, SW, OW, BW can substantially be made of a materialsubstantially non-transparent for light detectable by detecting membersD, of course except for transparent portions t and transparent regions3.

Wafers SW and BW and possibly also all or a portion of wafer OW can beproduced by replication. In an exemplary replication process which canalso be used for manufacturing precursor wafer 8 or transparent elements6, a structured surface is embossed into a liquid, viscous orplastically deformable material, then the material is hardened, e.g., bycuring using ultraviolet radiation or heating, and then the structuredsurface is removed. Thus, a replica (which in this case is a negativereplica) of the structured surface is obtained. Suitable materials forreplication are, e.g., hardenable (more particularly curable) polymermaterials or other replication materials, i.e. materials which aretransformable in a hardening step (more particularly in a curing step)from a liquid, viscous or plastically deformable state into a solidstate. Replication is a known technique, cf., e.g., WO 2005/083789 A2 orUS 2011/0050979 A1 for more details about this.

FIG. 14 is a schematized cross-sectional view of a device being a waferstack 2 for manufacturing a multitude of modules 1 of FIG. 12.

In order to form a wafer stack 2, the wafers BW, OW, SW, PW are alignedand glued together, e.g., using a heat-curable epoxy resin. The aligningcomprises aligning the substrate wafer PW and the optics wafer OW suchthat each of the detecting members D is aligned with respect to at leastone of the transparent portions t, in particular wherein each of thedetecting members D is aligned in the same way to one of the transparentportions t each, and the same applies to the light emitters E.

The thin dashed rectangles indicate where separation takes place, e.g.,by means of a dicing saw.

Although FIGS. 3 to 7 and 13 and 14 only show provisions for threemodules 1, there can be in one wafer stack provisions for at least 10,rather at least 30 or even more than 50 modules in each lateraldirection.

It is to be noted that it is possible to think of devices which comprisean optics member O, wherein the optics member is not comprised in anopto-electronic module 1.

It is further to be noted that the passive optical components L obtainedin a manner described above are not unitary parts. They comprise atleast two, e.g., two or three constituents, namely transparent element 6and optical structures 5 attached thereto. Transparent element 6,however, can be a unitary part.

A semi-finished part (which can in a certain view also be a deviceaccording to the invention) obtained by providing the transparentelements 6 in a precursor wafer 8 can be a flat disk-like wafer havingno holes penetrating the wafer (or at least no holes penetrating thewafer in the regions where the transparent portions t are).

The semi-finished part can have virtually no or only shallow surfacecorrugations in those regions, wherein such surface corrugations, ifpresent, can be, for example, concave (cf. FIG. 10), i.e. do not extendbeyond the wafer surface as described by the at least one blockingportion b. Convex meniscuses possibly formed can be flattened, e.g., asdescribed above, by polishing, so as to obtain a transparent element 6having parallel surfaces adjusted to the wafer thickness, whereinpossibly also the wafer thickness can be adjusted (reduced).

But: The semi-finished part can alternatively have a structured surface,on one or on both sides, in particular in those regions where thetransparent portions t are. There can be wanted corrugations in blockingportion b. In particular, it is possible that a wafer, a “combinedoptics wafer”, is provided which is a combination of an optics wafer(such as the described optics wafer OW) and a spacer wafer (such as thedescribed spacer wafer SW). Accordingly, then, the spacer wafer isoptional, its properties and functions are fulfilled by an optics wafer(“combined optics wafer”) structured and configured accordingly. Thiscan be accomplished, e.g., by manufacturing as a unitary part: what isdescribed above as spacer wafer SW and what is described above as atleast one blocking portion b. A corresponding optics wafer (“combinedoptics wafer”) can be readily visualized when looking upon wafers OW andSW in FIG. 14 as one single part. Starting from a suitable semi-finishedpart, a “combined semi-finished part”, a “combined optics wafer” can beobtained by producing thereon (on transparent portions of the “combinedsemi-finished part”) optical structures, e.g., in a way as describedabove, e.g., by dispensing.

Another example of a “combined semi-finished part” (referenced ow′) isillustrated in FIG. 16, whereas a semi-finished part ow which moreclosely corresponds to what is described in conjunction with FIGS. 3 to7 and 12 to 14 is illustrated in FIG. 15.

Furthermore an optics wafer (“combined optics wafer”) can be providedwhich is a combination of an optics wafer (such as the described opticswafer OW) and a baffle wafer (such as the described baffle wafer BW).Accordingly, then, the baffle wafer is optional, its properties andfunctions are fulfilled by an optics wafer (“combined optics wafer”)which is structured and configured accordingly. This can beaccomplished, e.g., by manufacturing as a unitary part: what isdescribed above as baffle wafer BW and what is described above as atleast one blocking portion b. A corresponding optics wafer can bereadily visualized when looking upon wafers OW and BW in FIG. 14 as onesingle part. A suitable “combined semi-finished part” might look similarto what is shown in FIG. 16.

Of course, it is also possible that both sides of an optics wafer(“combined optics wafer”) are structured. E.g., so as to make, in theembodiment of FIG. 14, baffle wafer BW and spacer wafer SW obsolete.

Filling-in of transparent material T into a single- or both-sidedlystructured precursor wafer for forming the transparent elements 6 (forobtaining a semi-finished part) can be accomplished similarly to what isshown in FIG. 4 (and what is implied in FIG. 16 by the support layer12), wherein in FIG. 16, a not-structured side of “combinedsemi-finished part” ow′ faces the support layer 12. Alternatively, astructured support layer 12 could be used during forming the transparentelements 6, for avoiding a (too intense) flowing-through of filled-inmaterial through the openings of the precursor wafer. The latter way ofproceeding can be particularly useful when a precursor wafer having astructured surface on both sides shall be provided with the transparentelements 6.

Corresponding to what has just been described for wafers, a “combinedoptics member” can also be provided. The blocking portion of an opticsmember can have a structured surface, in particular a surface withprotruding portions protruding vertically beyond a surface of atransparent element of the “combined optics member”. It is possible thata member (“combined optics member”) is provided which is a combinationof the above-described optics member and the above-described separationmember (or a combination of the described optics member and thedescribed baffle member, or a combination of all three). Accordingly,then, the separation member (and/or the baffle member) is optional, itsproperties and functions are fulfilled by an optics member which isstructured and configured accordingly. This can be accomplished, e.g.,by manufacturing as a unitary part: what is described above asseparation member S (and/or what is described above as baffle member B)and what is described above as at least one blocking portion b.

A usual consequence of providing such a “combined optics member” or“combined optics wafer” is that the number of parts (of an item to beconstructed, such as of a module 1) and the number of assembly steps isreduced, and less aligning errors will usually occur.

Coming back to FIG. 15, the semi-finished part ow shown there can besubjected to a polishing step on one or on both sides. The polishingstep can be accomplished, e.g., for thinning the wafer ow (precisely) toa desired thickness, and/or for improving the optical properties (atleast of the transparent elements 6). Of course, also a one-sidedlystructured semi-finished part can be polished, at least on its flat(not-structured) side. Furthermore, it is to be noted that it ispossible to polish precursor wafers, on one or both sides, at least onat least one flat side. Doing so not only possibly contributes to aflatter and/or more even surface of the precursor wafer, but may allowto reduce the thickness of the precursor wafer to a desired thickness,which may be helpful in possible subsequent manufacturing steps.

If a semi-finished part (“combined” or not) is itself a device and shallbe used without producing optical structures on the transparent elements6, it can be useful to polish one or both sides, for achieving anoptical grade surface, in particular a surface being particularly planeand having a particularly small surface roughness.

When, for obtaining an optics wafer, optical structures 5 are applied(e.g., by means of replication) to a semi-finished part, where concavemeniscuses of the transparent material T are present, the replicationcan take place on these meniscuses, wherein the amount of appliedreplication material might have to be adjusted accordingly. If acorresponding semi-finished part is polished, well-defined flat surfacescan be obtained, and less variation is provided for subsequentreplication steps. Thus, replication is likely to be carried out easierand/or can lead to a more stable (and reproduceable) process and to apossibly better precision.

The materials which are hardened, for example, cured, during amanufacturing process described anywhere above can be polymer-basedmaterials such as epoxy resins.

Due to manufacturing on wafer-level, most alignment steps are carriedout on wafer-level making it possible to achieve a very good alignment(in particular of members D and E with respect to passive opticalcomponent L) in a rather simple and very fast way. The overallmanufacturing process is very fast and precise. Due to the wafer-scalemanufacturing, only a very small number of production steps is requiredfor manufacturing a multitude of modules 1 and/or a multitude of opticsmembers O.

The optics member O (and also the other addressed devices) can be usefulin many applications, in particular where apertures are applied and/orwhere protection from light is sought, and/or where mass production isnecessary and/or where particularly small optical members (or passiveoptical components) are needed.

Other implementations are within the scope of the claims.

LIST OF REFERENCE SYMBOLS

-   1 device, opto-electronic module-   2 device, wafer stack-   3 transparent region-   4 opening-   5 optical structure, lens element-   6 transparent element-   7 solder ball-   8 precursor wafer-   9 printed circuit board-   10 device, electronic device, smart phone-   11 hole, opening-   12 support layer-   13 support substrate-   b blocking portion, non-transparent portion-   B baffle member-   BW baffle wafer-   D detector, light detector, photo diode-   E light emitter, light-emitting diode-   L passive optical component, lens member-   device, optics member-   ow device, semi-finished part-   ow′ device, semi-finished part, “combined semi-finished part”-   OW device, optics wafer-   P substrate-   PW substrate wafer-   S separation member-   SW spacer wafer-   t transparent portion-   T transparent material

What is claimed is:
 1. A method for manufacturing a wafer comprising atleast one blocking portion and a multitude of transparent elementswherein each of said multitude of transparent elements is made of one ormore materials substantially transparent for light of at least aspecific spectral range, referred to as transparent materials, and saidat least one blocking portion is made of one or more materialssubstantially non-transparent for light of said specific spectral range,referred to as non-transparent materials, wherein at least one of thefollowing applies with respect to the wafer: (A) a vertical extension ofeach of said multitude of transparent elements is at least approximatelyequal to a vertical extension of said at least one blocking portion,wherein each of the transparent elements has two opposing at leastapproximately flat surfaces substantially perpendicular to a verticaldirection; (B) the at least one blocking portion together with thetransparent elements describes a solid plate-like shape with opposingflat surfaces; (C) the wafer has an extension in the vertical direction,which is small with respect to the wafer's extension in the other twodirections, wherein each of the transparent elements has two opposingflat surfaces perpendicular to the vertical direction, wherein the twoopposing flat surfaces are arranged in a distance equal to a thicknessof said at least one blocking portion measured along the verticaldirection; and wherein the method comprises: d1) providing a precursorwafer substantially made of said non-transparent material havingopenings in places where said transparent elements are supposed to belocated; d2) at least partially filling said openings with at least oneof said transparent materials.
 2. The method according to claim 1,wherein d2) is carried out using a dispenser.
 3. The method according toclaim 1, comprising manufacturing said precursor wafer usingreplication.
 4. The method according to claim 1, comprising carrying outpolishing after accomplishing d1) and d2).
 5. The method according toclaim 1, wherein, during d2), the at least one transparent material isin a liquid or viscous state.
 6. The method according to claim 5,comprising carrying out subsequent to d2), d3) hardening saidtransparent material.
 7. The method according to claim 6, wherein d3)comprises curing said transparent material.
 8. The method according toclaim 1, wherein d2) is carried out using a squeegee process.
 9. Themethod according to claim 1, comprising creating said openings by meansof drilling or etching.
 10. The method according to claim 1, comprisingmanufacturing said precursor wafer using molding.
 11. The methodaccording to claim 1, wherein the precursor wafer is a blank wafer. 12.A method for manufacturing a device, the method comprising: a) providinga wafer comprising at least one blocking portion and a multitude oftransparent elements; wherein each of said multitude of transparentelements is made of one or more materials substantially transparent forlight of at least a specific spectral range, referred to as transparentmaterials, and said at least one blocking portion is made of one or morematerials substantially non-transparent for light of said specificspectral range, referred to as non-transparent materials, and wherein atleast one of the following applies with respect to the wafer: (A) avertical extension of each of said multitude of transparent elements isat least approximately equal to a vertical extension of said at leastone blocking portion, wherein each of the transparent elements has twoopposing at least approximately flat surfaces substantiallyperpendicular to a vertical direction; (B) the at least one blockingportion together with the transparent elements describes a solidplate-like shape with opposing flat surfaces; (C) the wafer has anextension in the vertical direction, which is small with respect to thewafer's extension in the other two directions, wherein each of thetransparent elements has two opposing flat surfaces perpendicular to thevertical direction, wherein the two opposing flat surfaces are arrangedin a distance equal to a thickness of said at least one blocking portionmeasured along the vertical direction.
 13. The method according to claim12, comprising manufacturing said wafer.
 14. The method according toclaim 13, wherein manufacturing said wafer comprises d1) providing aprecursor wafer substantially made of said non-transparent materialhaving openings in places where said transparent elements are supposedto be located; d2) at least partially filling said openings with atleast one of said transparent materials.
 15. A method for manufacturinga wafer comprising at least one blocking portion and a multitude oftransparent elements wherein each of said multitude of transparentelements is made of one or more materials substantially transparent forlight of at least a specific spectral range, referred to as transparentmaterials, and said at least one blocking portion is made of one or morematerials substantially non-transparent for light of said specificspectral range, referred to as non-transparent materials, wherein atleast one of the following applies with respect to the wafer: (A) avertical extension of each of said multitude of transparent elements isequal to a vertical extension of said at least one blocking portion; (B)the at least one blocking portion together with the transparent elementsdescribes a solid plate-like shape with opposing flat surfaces; (C) thewafer has an extension in one direction, referred to as verticaldirection, which is small with respect to the wafer's extension in theother two directions, wherein each of the transparent elements has twoopposing flat surfaces perpendicular to the vertical direction, whereinthe two opposing flat surfaces are arranged in a distance equal to athickness of said at least one blocking portion measured along thevertical direction; and wherein the method comprises: d1) providing aprecursor wafer substantially made of said non-transparent materialhaving openings in places where said transparent elements are supposedto be located; d2) at least partially filling said openings with atleast one of said transparent materials.
 16. The method according toclaim 15, wherein d2) is carried out using a dispenser or using asqueegee process.
 17. The method according to claim 15, comprisingmanufacturing said precursor wafer using replication.
 18. The methodaccording to claim 15, comprising carrying out polishing afteraccomplishing d1) and d2).
 19. The method according to claim 15,wherein, during d2), the at least one transparent material is in aliquid or viscous state.
 20. The method according to claim 15,comprising carrying out subsequent to d2), d3) hardening saidtransparent material.
 21. The method according to claim 15, comprisingcreating said openings by means of drilling or etching.
 22. The methodaccording to claim 15, wherein the precursor wafer is a blank wafer. 23.A method for manufacturing a device, the method comprising: a) providinga wafer comprising at least one blocking portion and a multitude oftransparent elements; wherein each of said multitude of transparentelements is made of one or more materials substantially transparent forlight of at least a specific spectral range, referred to as transparentmaterials, and said at least one blocking portion is made of one or morematerials substantially non-transparent for light of said specificspectral range, referred to as non-transparent materials, and wherein atleast one of the following applies with respect to the wafer: (A) avertical extension of each of said multitude of transparent elements isequal to a vertical extension of said at least one blocking portion; (B)the at least one blocking portion together with the transparent elementsdescribes a solid plate-like shape with opposing flat surfaces; (C) thewafer has an extension in one direction, referred to as verticaldirection, which is small with respect to the wafer's extension in theother two directions, wherein each of the transparent elements has twoopposing flat surfaces perpendicular to the vertical direction, whereinthe two opposing flat surfaces are arranged in a distance equal to athickness of said at least one blocking portion measured along thevertical direction.
 24. The method according to claim 23, comprisingmanufacturing said wafer.
 25. The method according to claim 23, whereinmanufacturing said wafer comprises d1) providing a precursor wafersubstantially made of said non-transparent material having openings inplaces where said transparent elements are supposed to be located; d2)at least partially filling said openings with at least one of saidtransparent materials.